NASA’s Curiosity rover detected previously unseen broad and shallow pits in its work areas this week, during its 14th year on Mars. The approximately 1 centimeter (0.39 inches) wide example pit was imaged by MAHLI on August 19, 2026, on Sol 4989, at 07:59:21 UTC. These pits are thought to have formed from voids left by nodules or pebbles that weathered out of the bedrock; unlike previous examples, however, they are broader and shallower, with no obvious remnants inside. MAHLI and Mastcam acquired images suitable for creating stereo mosaics and a digital elevation model to examine the structures.
Mastcam and ChemCam examined layers showing changes in texture and structure over short vertical intervals. ChemCam, MAHLI and APXS analyzed gray, rough and resistant layers that could indicate chemistry different from the bedrock. ChemCam also investigated the origin of gray rocks scattered across the work areas. The visible face of “Cordillera” hill was mosaicked with Mastcam; ChemCam imaged specific layers. The “Tolhuaca” and “Potosí” hills were also examined. The team increased REMS, Mastcam and Navcam observations to monitor a possible regional dust storm.
Why it matters
The fact that the new pits are wider and shallower than previous examples requires the current explanation for their formation to be considered alongside different surface conditions. The absence of clearly visible remnants within them provides a new point of comparison for examining cavities left in the rock by nodules or pebbles that became detached through erosion. Examining layers, gray rocks and surfaces indicating chemistry different from the bedrock within the same work area together is providing data that could reveal how variable the Martian terrain is in terms of texture and composition. However, the exact formation process of these structures, the origin of the gray rocks and how the observations will be affected by the possible dust storm being monitored remain open questions.